As a technique of this type, Patent Literature 1 discloses a technique in which, as shown in FIG. 30 of the present application, an input terminal 100 to be connected to a battery and a bus bar 102 including tab-like output terminals 101 are accommodated in a box 103 in a state where they are prevented from being disengaged from each other. In Patent Literature 1, a resin mold portion 104 which sandwiches the front and back surfaces of the bus bar 102 is provided and projections 105 which are respectively provided on the right and left sides of the resin mold portion 104 are elastically engaged with lock pieces 106 which are provided on right and left wall surfaces of the box 103.